Simple reason is because everyone cannot afford to. Thats what this is all about. In order to take care of yourself the food you need to maintain good health should cost less than a meal at McDonalds. The reason health care costs so much currently is because of the combination of law suits, uninsured people, and bad health practises. The sooner people understand this the better off everyone will be.
Do you really want someone working on your health that is in it only for the money? We wont have a dearth of doctors just like it wont happen with teachers because there will always be people that give of themselves to help maintain health and educate.
That is ridiculous, considering the skill required for providing health care vs. the skill required to serve a Big Mac. Health care costs so much because of the skill required to provide it, and yes, the downside if something doesnt work out right.
And your whole "bad health practices" thing is another reason you dont want government control of your healthcare, because if they are the only option, they can decide what you like to do isnt cost effective and deny treatment. and who are you going to go to or use to stop them? You would be "paying" for it with your taxes, but they will decide they can deny you service. Dont like it? Go to some feckless burecrat to complain, they can probably wait you out.
I WANT my doctors to be in it for the money, considering how much schooling they have to go through. Teachers go through 1/4 of the training required for even a general practicioner, nevermind a specialist or surgeon. Of course we pay them less we either get less skillful people, or we lower the standards to justify lowering thier training.